The heavy top tanning unit of a tanning bed is difficult for many people to raise and lower. A simple hinge mechanism on the tanning unit restrains the motion of the tanning unit to rotation about the axis of the hinge. The top tanning unit is to be moved by applying a force to the top tanning unit such that a sufficient torque is produced about the axis of the hinge to over-balance the torque caused by gravitational forces acting on the mass of the tanning unit. A person can direct the force required to raise the tanning unit about the axis of the hinge to maximize the torque. Therefore, a simple hinge mechanism can be an efficient means of lifting or lowering a tanning unit.
When the tanning unit is massive, however, the force required to lift the tanning unit or to gently lower the tanning unit is great. The abstract efficiency of the hinge is little consolation to a person trying to handle a heavy hinged tanning unit.
Furthermore, some people are claustrophobic and do not like to have the tanning unit in the fully lowered position. Therefore, it would be a valuable contribution to the art to provide a tanning unit which can be retained in any instantaneous position between a first lowered position and a second raised position.
Finally, traditional mechanisms for supporting the top unit of a tanning bed are obtrusive and unreliable. Most of the current mechanisms employ gas cylinders which are highly sensitive to the ambient temperature. Therefore, these mechanisms work over a rather narrow temperature range. The tanning unit radiates sufficient heat that the ambient temperature fluctuates significantly. It is extremely irritating to the person using the tanning unit when the tanning unit will not stay in a desired position. These gas cylinders are usually attached toward the front of the tanning unit which interferes with free access to the tanning bed.